Improvement in driers



C. H. HERSEY.

DRIBR.

. Patented Apr. 25, 1871.

UNITED STATES CHARLES H.

PATENT GFFIGE.

HERSEY, OF BOSTON, MASSACHUSETTS, ASSIGFOR TO 'HAWES & HERSEY, OF SAME PLACE.

IMPROVEMENT IN DRIERS.

Specification forming part of Letters Patent No. 114,137, dated April 25, 1871,.

.To all whom 'it may concern:

Be it known thatjI, CHARLES H. HERsEY, of Boston., in the county of Suffolk and State of Massachusetts, have invented an Improved Drying Apparatus; and I do hereby-declare that the following, taken in connect-ion with the drawing which accompanies and forms part of this specification, is a description of my invention sufficient to enable those skilled in the art to practice it.

My invention relates to the organization of -a tubular rotary drying apparatus for drying sugar, salt, grain, and other line substances.

lIn my construction I employ a hollow cylinder or tube, mounted in a somewhat inclined 'position upon friction-rollers, and so as to be capable of free rotation thereupon, this tube being the holder and conveyer, upon the inner surface of which the material is received, and through which it passes to be dried. Centrally Within this tubular conveyer I place a heater-cylinder, held in position relatively and concentrically to the conveyer by suitable spokes, (which are preferably made adjustable to bring the heater to proper position relatively to the conveyer,) and having tight heads at its opposite ends, a steam-pipe connecting with one end and admitting steam from a suitable boiler into the heater-cylinder, and an outlet-pipe, permitting steam to pass from said cylinder.

Steam being supplied to the heater-cylinder, and the outer cylinder being put in rota tion, the material to be dried is let into the highest and open induction end of the cylinder. Air passes freely through the cylinder, and, by contact with the heater-cylinder, suoli air is quickly heated thereby, and the sugar, salt, or other material has its moisture taken up by the dry and heated air passing through the cylinder and heated by contact with the heater-cylinder, while the contact of the matelrial with the surface of the heater-cylinder warms it and assists it in giving offits moisture.

It is in a drier having a hollow and rotary conveyer cylinder or drum,with a centrally or concentrically located steam drier cylinder, that my invention primarily consists, the combination of the rotary drum and a central and lrotary steam-drier cylinder Within the drum,

(the two cylinders being connected and rotating as one,) the method of connecting the two cylinders, the arrangement of the take-up flanges within the drier-cylinder, the arrangement of rings and jarring-weights within the heater-cylinder, the arrangement of a pipe for expelling from the steam-cylinder the Water of, condensation, and the speciec onstruction of the outer cylinder with reference to the provision for its rotation, constituting minor features of the invention.

' The drawing represents, in longitudinal vertical section and in vertical cross-section, a drying apparatus embodying the invention. a denotes the conveyor-cylinder or open-ended drum, into which the material to be dried is fed, and through and by which it is conveyed for the drying process. Around the cylinder are encompassing-rings I1, having peripheral treads o, each tread o being supported-upon two friction wheels or rolls, d, turning on pins c mounted. in stands e', the stands at one end of the machine being higher than those at the opposite end, so that the drum is supported in an inclined position, as shown at A, to facilitate the progressive movement of the material-through .the drum. This drum is open at both ends, so that a current of air and the material to be dried can both pass freely through it, and centrally within it is placed the heater-cylinder or steam-heater f. The -`heater j' is made with heads g, made steam-tight, except for entrance of a steampipe, h, into one end of the heater and for Water-escape pipe i at the opposite end, these pipesbeing controlled by suitable valves and cocks. The heater-cylinder is connected with the main drum hy a series of radial spokes, lo, (each preferably made with provision for adjustment of its length by means of a screw, Z, and nuts 012,) to correctly locate the heater concentrically within the drum, and to tighten the parts so that there can be no relative movement'.

Within the drum is a series of blades or buckets n, extending longitudinally through the drum, and by these buckets the material ied into the induction end of the drum and ialling to the bottom of the drum is taken up as they rotate, and carried around with them until each' bucket reaches such position as to cause the material" to drop by gravity. '.lo

line of buckets causes the material to drop from it at one point, the angle of the next may cause'the material to be carried a little farther on, or not quite so far 0n,.and thus the material ldrops nearlyall the way across the cylinder. As most "of itdrops it falls upon the heater-cylinder, and'becomes heated and dries to some extent by such contact therewith. The heater-cylinder beingkept charged with hot steam, the' cylinder is heated, and the heat radiated from its outside warms the current of air passing through the drum, and this air absorbs the moisture of the material raisedy through it, so that the material emerges cris discharged from the eduction end of the con- ,veyer ordrum in a perfectly dry condition. As someof the material may havea tendency to adhere to the surface of the heater-cylinder, l place Within said cylinder rings o, parallel with the heads, and between these rings are radial-blades p; and in the spaces thus made I place 4heavy balls q, which, being taken up by the blades, drop to the bottom of the cylinder when the blades can no lon ger hold them, and by these fallin g balls the cylinder is constantly jarred, and the material is thereby dislodged from its outer surface.

I am aware that a rotary drier-drum has been madewith provision for driving a current of heated air through the drum and the material to be dried, as is seen in United States Patent No. 90,549. i

I am also aware thata rotary drier-drum or cylindrical chamber has been located within a stationary chambered cylinder, heated by v steam or other suitable heating medium v as is seen in United-States Patent N o. 55,098.

My construction differs from these particularly in that I employ a rotary drum or opens ended conveyer-tube for passage of the material and the currents of air, in connection with a central andconcentric heater-cylinder running through the drum, and equally heated at all points of its surface by thel contact and pressure of the steam driven through it. .This steam maybe superheated, if desirable.

' The water of condensation is expelled, by the pressure of the steam, through the pipe i., said pipe passingaxially into the heater, and then bending and extending to the bottom of the heater, the cylinder `rotating upon the axial portion of the pipe, so that the.`vertical leg r' remains stationary. This pipe is connected with a steamtrap that preventsescape of steam from the heater.

At the induction end of the cylinder there may be a chute or hopper for guiding the material into the heater, and at'the. opposite ena a suitable spout for conducting ott' the dried material.

1. A rotary drier-drum open at its opposite ends, and having located centrally within it a steamheated cylinder for heating the currents of air passing through the drum andthe material'falling upon the heater.

2. The rotarydruin aand heaterLcylinderf, connected together and held in relative position by the spokes 1r, substantially as shown and described.-

3. The adjustable spokes k, in combination as shown and described.

'6. The rings o and iianges p, in combination Withthe heater-cylinder, and for raisingl the balls and letting them drop, substantia described.

Executed March 1l, 1871. CHAS. H. HERSEY.

yas

Witnesses:

M. W. FROTHINGHAM, FRANCIS GoULn. 

